/data/retesteth/build/retesteth/retesteth -t DifficultyTests -- --all -j2 --nologcolor --exectimelog --clients t8ntool --testpath /data/tests 
Running tests using path: /data/tests
Running 7 test cases...
Retesteth config path: /home/ubuntu/.retesteth
Active client configurations: 't8ntool '
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfArrowGlacier": (1 of 7)
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Tests finished: 5
dfArrowGlacier time: 75.23, cputime: 2.89 (3%), t8ntime: 143.25 (190%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfByzantium": (2 of 7)
100%
Tests finished: 1
dfByzantium time: 89.39, cputime: 2.00 (2%), t8ntime: 87.74 (98%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfConstantinople": (3 of 7)
100%
Tests finished: 1
dfConstantinople time: 91.60, cputime: 2.06 (2%), t8ntime: 89.91 (98%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfEIP2384": (4 of 7)
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Tests finished: 3
dfEIP2384 time: 115.76, cputime: 4.48 (3%), t8ntime: 217.95 (188%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfFrontier": (5 of 7)
100%
Tests finished: 1
dfFrontier time: 87.34, cputime: 1.97 (2%), t8ntime: 85.72 (98%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfGrayGlacier": (6 of 7)
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Tests finished: 5
dfGrayGlacier time: 80.91, cputime: 2.63 (3%), t8ntime: 126.24 (156%)
Running tests for config 'Ethereum GO on StateTool' 2
Test Case "dfHomestead": (7 of 7)
100%
Tests finished: 1
dfHomestead time: 90.91, cputime: 2.08 (2%), t8ntime: 89.20 (98%)

*** No errors detected
*** Total Tests Run: 17

*** Execution time stats
Total Time:                               : 631.14          :   18.12 (2%)              :  840.01 (133%)
dfEIP2384                             time: 115.76   cputime:    4.48 (3%)       t8ntime:  217.95 (188%)
dfConstantinople                      time: 91.60    cputime:    2.06 (2%)       t8ntime:   89.91 (98%)
dfHomestead                           time: 90.91    cputime:    2.08 (2%)       t8ntime:   89.20 (98%)
dfByzantium                           time: 89.39    cputime:    2.00 (2%)       t8ntime:   87.74 (98%)
dfFrontier                            time: 87.34    cputime:    1.97 (2%)       t8ntime:   85.72 (98%)
dfGrayGlacier                         time: 80.91    cputime:    2.63 (3%)       t8ntime:  126.24 (156%)
dfArrowGlacier                        time: 75.23    cputime:    2.89 (3%)       t8ntime:  143.25 (190%)